Machine for making composite sheets



Dec. 24, 1929. L. MCCARTHY MACHINE FOR MAKING COMPOSITE SHEETS Filed Nov. 4. 1926 :Visa

A+? ys Patented Dec. 24, 1929 UNITED sTATEs PATENT OFFICE LOUIS MCCARTHY, F BOSTON, MASSACHUSETTS, ASSIGNOR TO THE MACALLEN COMPANY, A CORPORATION OF MASSACHUSETTS MACHINE FOR MAKING COMPOSITE SHEETS Y Application filed November 4, 1926.

This invention relates to machines for forming composite sheets by the use of an adhesive binder, and especially, although not exclusively, to machines, of the type shown in a prior application filed November 6, 1922, Serial No. 599,248, patented March 29, 1927, No. 1,622,795-, for forming composite mica sheets. A machine of this type comprises a suitable elongated bed on which is disposed a flexible belt and over which is arranged to travel a carriage having means for showering the mica flakes on the belt, means for applying a liquid adhesive binder to therfialres so deposited, and means for rolling the flakes l5 and binder on the belt to unite them into a composite sheet. Such a machine also in zludes a winding drum or reel upon which the ends of the belt may be wound after the Y completion of the sheet to draw the belt Yover the bed and about the end thereof and thereby discharge the finished sheets, a second and similar drum or reel being provided to return the belt to its normal position on the bed after the sheets have been discharged.

In the operation of a machine of this type, more or less of the adhesive binder accumulates upon the operative upper surface of the belt, or that portion thereof upon which the composite sheets are formed, and when the belt is wound upon the reel or drum in interengaging convolutions, more or less of this adhesive material is transferred to the opposite or under surface of the belt, that is to say, the surface which engages the bed. This causes adhesion between the belt and the bed, makingit difficult to draw the former over the latter in the normal operation of the machine, and also causes quantities of adhesive to accumulate on the bed itself, making it necessary to clean the latter at frequent intervals with consequent interruption to the operation of the machine. The present invention has for its object to overcome the'difriculties last referred to, and to this end contemplates a construction, including a belt and a winding drum or reel Ather'efor,jin which, however, the operative portion of the belt, or that portion upon which the sheets areformed and upon which 5 the adhesive binder'te-nds to accumulate, is

Serial No. 146,178.

not wound upon the drum or reel, so that no transfer of the adhesive material from the upper to the lower' face of the belt occurs.

The foregoing and other objects of the invention, together with means whereby the latter may be carried into effect, will best he understood from the following description of a preferred form thereof illustrated in the accompanying drawings. .It will be understood, however, that the particular construction described and shown has been chosen for purposes of exemplification merely, and that the invention, as defined by the claims here unto appended, may be otherwise embodied without departure from the spirit and scope thereof.

In said drawings:

Fig. 1 is a side elevation of substantially the complete machine.

Fig. 2 is a plan view, partly broken away, of the bed, belt, and associated devices.

Fig. 3 is an enlarged side elevation of the yielding belt take-up, showing the parts in the positions assumed under tension.

The machine shown in Figs. 1 and 2 comprises yan elongated bed 10 carried by suitable supports 11 and over which is adapted to travel, on suitable ways supported thereon, a carriage 12 having rotating foraminous drums or other means, indicated at 13, for showering the mica flakes on the bed, means, indicated at- 14, for supplying adhesive binder in liquid form, and rollers 15 for rolling the flakes and binder on the bed as said carriage travels over the latter. Overlying the bed 10, and constituting a receiving member for the flakes and binder on which the former are united by the latter into composite sheets, is a flexible belt 16 which passes about guide rollers 17 at the ends of the bed, the ends y of said belt being wound upon drums or reels 18 and 19 respectively. One end of the bed, in the present instance the end shown at the right in Fig. 1, is the discharge or delivery end, and adjacent the guide roller 17 at that end is a suitable cutter 20 for dividing the finished sheets into sections which may be discharged into a suitable tray or other receiver 21. The reel 18 is located adjacent the delivery end of the machine and may be driven, as by a belt 22, from any suitable source of power (not shown) under the control of a clutch 23. The reel 19, as shown, is driven by an electric motor 24:, the controlling switch for which may also be conveniently located adjacent the delivery end of the machine.

In operation, when the mica flakes have been deposited to the desired depth upon the belt 16 and united into a Vcomposite sheet 'of the desired thickness, the travel Voi the carriage 12 is stopped and the finished sheet discharged. To this end, the clutch 28 is operated to cause the reel 18 to draw the belt 16 over the roller 17 at the delivery end of the bed., this abrupt bending of the belt .causing the sheet yto leave the same and extend into the receiver 21. The clutch :23 is .then released and the cutter .operated .to cut off a section `ot' the sheet, and these `operations repeated until the entire sheet has been .discharged and lc-ut ,up into sections of .convenient size. The reel 19 is then operated by the motor 24 to Vrewind the belt and restore .it to its original position on the .bed .10..

Except ashereinafter pointed out, the parts above mentioned .may all Vbe ,substantially as more fully shown and described in the =prior application above reterred to. i

.In @accordance with the .present invention, the belt 16 comprises an operative or .sheet receiving portion 25, corresponding` substantially in length and width to the .bed 10.1and

extensions 26 and 27, preferably of reduced width, constituting flexible connectors between the operative portion of the belt and the reels 18 and 19 respectively. The .length of each extension 26 and 27 is approximately equal tothe length of .the operative ,portion 25, and consequently to the length of the bed 10, so that the total length of the belt is approximately th-ree times that of said operative .portion and bed. When the belt is in its normal or operative position overlying the bed, .as

a shown in Fig. 2, the portion .or extension 2.7

thereof is substantially completely wound upon thc reel. 19, while the ,portion or extension 26 will be substantially completely unwound, the latter portion, which intervencs between the reel 18 and the corresponding end of the bed, being substantially vequal to the length of the operative portion and of thc bed. lhen the reel 18 4is operated :to draw the bell? over the bed and discharge :the-sheet.y

- the portion 26 only of said belt will be wound .on said reel, and the #forward .endot1 the operative portion 25 will not reachsaidreel until vthe rear end of said operative portionhasibeen .brought to the delivery end-otthebed andthe vthe belt 'is Wound upon said reel. It will therefore be seen that, While the reels 18 and 219 .operate .eectnally 'to .move the heltjn the desired manner, the operative portion of said belt is at no time wound upon said reels, so that transfer of the accumulated adhesive binder from the upper to the lower surface thereof, as well as adhesion between the belt and bed, is eectually prevented.

In order that the rleel 18 may be located in a convenient position adjacent the delivery end of the machine, the portion 26 of the belt between said reel andu the adjacent guide roller 127 may, as shown, be guided over a roller 28 in two approximately parallel stretches beneath the bed. In view of the added length of the belt, and for the purpose of holding the latter suitably taut, while preventingunduestrains thereon due to the sudden starting and stopping of the reel 18 `by the clutch 23, a suitable yielding italie-up is .preferably provided. As shown, the bottom stretch .of the portion 2 6 of the belt passes `rover a series oit-guide rollers 29 between .two

of .which it is deflected by ayfieldfingly mounted take-up roller 30. `Each .end of the roller 30 yis -`guided ,between a pair .of vertical posts `32 which rise from asuita-ble base 34 and are connected at their tops .by ia fixed ,cross-.head 85,. Above the roller :80 .isaslide or movable cross-head .86 guided fon the posts V32 and between which and `the fixed cross-head 35 are interposedsprings 3l mounted on `said posts. A second slide .or'movable .cross-head 37 is guided `on the ,posts .32 below Athe roller `30 and is supported ,by springs ,33 `on said posts and interposed between sazid cross-head and `the base .34. When the belt 16 is at rest, and as shown in Fig. iL, the ends .ofthe roller 3.0 are supported on the cross-heads37 and support the cross-heads 36. Vhen .the reel 18 is suddenly started, the resulting tensionon .the belt causes the latter to lift the roller 30 and cross-heads 36, this movement being yieldingly checked, and the strain on thebelt being consequently cushioned,by the springs 3l. 1When the reel is stopped, `the resulting slack in the belt is taken up by downward movement of the roller 30, the descent of the latter being cushioned by .the springs .33.

Having thus described my invention, l claim:

1. In a machine for Vforming composite.;

sheets by the use of a-n adhesvie'binder, a bed, a .flexible belt normally overlying said ,bed and on which the sheets `are formed, anda reelon which said beltis wound to draw the same o-ver said bed, `said belt being of suilicicnt length to permit .the .operative portion thereof on which the sheetsare formed .to .be completely withdrawn from said .bed without winding .any of said operative portion upon said reel.

'42. In a machine :for forming L composite sheets by the use ofanadhesizebinder, abad, a flexible belt normally overlying said bed and. on which .the .Sheets .are termed, .and a reel on which saidbeltlis wound .to .draw .the

saine over said bed, said belt having a portion extending between said bed and reel of sufficient length to permit the operative portion thereof 0n which the sheets are formed to be completely withdrawn from said bed without winding any of said operative portion upon said reel.

3. In a machine for forming composite sheets by the use of an adhesive binder, a bed, a iexible belt normally overlying said bed and having an operative portion on which said sheets are formed, and winding means for drawing said belt over said bed, said belt having an extension of approximately the length of the operative portion thereof and cooperating with said winding means.

4. In a machine for forming composite sheets by the use of an adhesive binder, a bed, a flexible belt normally overlying said bed and on which said sheets are formed, and a reel on which said belt is wound to draw the same over said bed, the portion of said belt extending between said reel and the end of said bed being approximately equal in length to the length of said bed.

5. In a machine for forming composite sheets by the use of an adhesive binder, a bed, a flexible belt normally overlying said bed and on which said sheets are formed, a reel onvwhich said belt is wound to draw the same over said bed, the portion of said belt between said reel and the end of said bed being approximately equal in length to the length of said bed, and means for guiding said belt in approximately parallel stretches beneath said bed.

6. In a machine for forming composite sheets by the use of an adhesive binder, a bed, a flexible belt normally overlying said bed and on which said sheets are formed, winding means for drawing said belt in one direction over said bed to discharge the finished sheets, and winding means for returning said belt to normal position, the length of said `belt between said winding means being ap proximately three times the length of said bed. i

- 7. In a machine for forming composite sheets by the use of an adhesive binder, a bed, a flexible belt normally overlying said bed and on which said sheets are formed, a reel on which said belt is wound to draw the same over said bed, the portion of said belt between said reel and said bed being approximately equal in length to the length of said bed, a clutch for controlling the operation of said reel, means for guiding said belt in approximately parallel stretches beneath said bed, guide rollers for one of said stretches, and a spring cushioned roller engaging said belt between two of said guide rollers.

In testimony whereof I affix my signature.

LOUIS MGCARTHY. 

